Conveyor systems are generally designed for specific applications wherein certain types of objects are moved between various points at various rates. These systems are often installed permanently in a facility, and perform the tasks for which they are designed quite well. However, such systems are not easy to modify. Therefore, if the manufacturing process or the type of material being conveyed changes, it may be necessary to remove the entire conveyor system or significant portions thereof and to replace it with a conveyor system specifically designed for the new task.
The need to modify a conveyor system arises particularly often in connection with conveyors for moving pallets. These pallets come in a variety of lengths and widths and can be loaded with different amounts of material. The size of a pallet is based on factors that are difficult to control, and therefore, it is difficult to standardize the pallet size. It is thus preferable to provide a conveyor system for handling different sizes of pallet rather than attempting to standardize the pallet size itself. However, designing a system that can accommodate the heaviest pallets that might be encountered requires the use of resources that are not necessary for conveying lighter loads. Likewise, it is difficult to adjust the width of a conveyor. Attempts to accommodate all types of pallet with one conveyor are generally not cost effective and do not work as well as a system that is configured to handle a particular type of pallet and load.
In order to overcome such problems, various modular conveyor systems have been proposed. Many of these modular systems comprise a number of conveyor segments which can be connected together to form a conveyor system. To use these systems, a number of different parts must be kept on hand or ordered each time a modification to the system is required. Furthermore, any time a length of conveyor is needed which can not be formed from a given number of segments, custom-made segments must be obtained. Segments removed from a system must be stored or discarded, and after several modifications, this can become quite expensive. Furthermore, none of these prior art systems allow the width of the conveyor system to be changed. Several of these systems are shown in the following United States Patents.
U.S. Pat. No. 4,146,126 to Mattos shows a modular conveyor system which includes a number of vertical supports connected together by support beams and side rails. In order to change the length of this conveyor it is necessary to remove the support beam and side rails and to replace them with new beams and rails of a suitable length. While this system may be easier to disassemble than previous systems, a change in configuration still requires the removal of large portions of the system and the replacement of this portion with new and possibly custom-made components. This system can not be rearranged easily, and to do so old parts must be discarded and new ones purchased or made.
U.S. Pat. No 5,096,045 to Feldl shows a portable conveyor system that suffers from the same shortcomings as the Mattos system described above. The Feldl conveyor includes a number of different sections, and sections can be added or removed to change the length of the conveyor, but specially made segments are still necessary in order to control the exact length of the conveyor. Furthermore, a segment once removed, must be discarded or stored, and the width of this conveyor cannot be changed.
U.S. Pat. No 5,131,531 to Chambers shows another modular conveyor having a number of bolted-together track segments. Like the above references, the length of the system can only be changed in increments of the length of one of the modules, and the width of the system is not adjustable.
None of the above conveyor systems have adjustable widths, and all are limited to a certain number of lengths and arrangements due to the fixed length of each segment in the system. Likewise, each of the segments is designed to support a certain maximum load and cannot be easily adjusted to accommodate heavier or lighter loads. It would therefore be desirable to provide a modular conveyor system wherein the width of the system can be changed as easily as the length, which can be formed in virtually any length without the need for custom parts, and which can quickly and easily be changed from one configuration to another.